Measles is a highly contagious viral disease caused by the measles virus. It spreads through the air by respiratory droplets and aerosols when an infected person coughs or sneezes. Symptoms include high fever, cough, runny nose, red eyes and a characteristic generalized rash.

Measles can occur at any age in people who are not immune but is most common and most severe in young children. Complications include ear infections, diarrhoea, pneumonia, encephalitis and blindness, and can lead to death. Disease and complications are more frequent and often more severe in malnourished children and in people who are immunocompromised. Because measles is so transmissible, population immunity of about 95% with two doses is needed to prevent outbreaks.

Live-attenuated measles vaccines are safe, effective and inexpensive, and have been in use since the 1960s. They are available as monovalent vaccines or in combination with rubella (MR), mumps and rubella (MMR), or mumps, rubella and varicella (MMRV) vaccines, and are referred to collectively as measles-containing vaccines (MCV). 

• WHO recommends that all countries include two doses of measles-containing vaccine in their routine immunization schedules.
• Countries should aim to reach and maintain at least 95% coverage with both doses in every district to achieve and sustain measles elimination.
  
• Where routine coverage is insufficient, supplementary immunization activities (SIAs) should be used to reach children who have not been vaccinated or who have received only one dose.
  
• Countries should strengthen surveillance to detect outbreaks early and respond rapidly with vaccination.
  
  

• The first dose (MCV1) should be given at 9 months of age in countries with ongoing measles transmission and a high risk of measles death among infants. In countries with low risk of transmission, MCV1 can be given at 12 months of age.
• The second dose (MCV2) should be given in the second year of life, at 15–18 months of age, or at school entry in countries with very low transmission and high coverage. The minimum interval between doses is 4 weeks.
• Countries do not need to meet previous coverage criteria before introducing a routine second dose.
• Children and adults who have not received two doses should be vaccinated to complete the schedule.